Ring Sizer

Find your perfect fit with our easy-to-use ring sizer guide. Measure at home using a printable chart or household items, then match your size to our sizing chart for accurate results every time.

Lunéa Paris · Sizing

Find your ring size,
right on this screen.

Calibrate your screen once, then measure a ring you already own — or your finger — to get an exact size in seconds. Nothing leaves your device.

Calibrate your screen

Hold a credit card or a US quarter flat against your screen and adjust the slider until the outline below matches its edges exactly. This makes every measurement that follows accurate to real-world millimetres.

Tip — set your browser zoom to 100%, keep the card flat against the screen with no case, and view it straight on rather than at an angle.

diag: viewport px · dpr · zoom · px/mm · touch

Place your ring — or measure your finger

Lay a ring you already own flat on the screen. Use the slider until the gold circle matches your ring's inner edge.

Place ring · match the inner edge

Use ← → arrow keys for fine adjustment

9 US size Diameter 17.0 mm · Circumference 53.4 mm

Wrap a thin strip of paper around your finger, mark where the ends meet, then lay it flat below — start at 0 and drag the marker to your mark.

Ruler in millimetres · line up the strip's start at 0

57.0
Drag the marker, or fine-tune here
9 US size Circumference 57.0 mm

Your ring size

Based on your measurement just now.

US size
UK
EU
Diameter (mm)

Between two sizes, or choosing an eternity band or wide setting? We generally recommend sizing up by half a size for comfort.

Not sure, or sizing for someone else? Our concierge team is happy to help — get in touch.

Size conversion, at a glance

USUKEUDiameter (mm)Circumference (mm)
5J4915.749.3
6L51.516.551.9
7N5417.354.4
8P5718.157.0
9R5919.059.5
10T6219.862.1
11V6420.664.6
12X66.521.467.2